[PATCH V4 06/27] ublk: add helper of __ublk_fetch()

Ming Lei
2025-11-21T01:59:36Z

Add helper __ublk_fetch() for refactoring ublk_fetch().

Meantime move ublk_config_io_buf() out of __ublk_fetch() to make
the code structure cleaner.

Reviewed-by: Caleb Sander Mateos <csander@purestorage.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
---
drivers/block/ublk_drv.c | 46 +++++++++++++++++++++-------------------
1 file changed, 24 insertions(+), 22 deletions(-)

diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c
index 5e83c1b2a69e..dd9c35758a46 100644
--- a/drivers/block/ublk_drv.c
+++ b/drivers/block/ublk_drv.c
@@ -2234,39 +2234,41 @@ static int ublk_check_fetch_buf(const struct ublk_device *ub, __u64 buf_addr)
return 0;
}

-static int ublk_fetch(struct io_uring_cmd *cmd, struct ublk_device *ub,
- struct ublk_io *io, __u64 buf_addr)
+static int __ublk_fetch(struct io_uring_cmd *cmd, struct ublk_device *ub,
+ struct ublk_io *io)
{
- int ret = 0;
-
- /*
- * When handling FETCH command for setting up ublk uring queue,
- * ub->mutex is the innermost lock, and we won't block for handling
- * FETCH, so it is fine even for IO_URING_F_NONBLOCK.
- */
- mutex_lock(&ub->mutex);
/* UBLK_IO_FETCH_REQ is only allowed before dev is setup */
- if (ublk_dev_ready(ub)) {
- ret = -EBUSY;
- goto out;
- }
+ if (ublk_dev_ready(ub))
+ return -EBUSY;

/* allow each command to be FETCHed at most once */
- if (io->flags & UBLK_IO_FLAG_ACTIVE) {
- ret = -EINVAL;
- goto out;
- }
+ if (io->flags & UBLK_IO_FLAG_ACTIVE)
+ return -EINVAL;

WARN_ON_ONCE(io->flags & UBLK_IO_FLAG_OWNED_BY_SRV);

ublk_fill_io_cmd(io, cmd);
- ret = ublk_config_io_buf(ub, io, cmd, buf_addr, NULL);
- if (ret)
- goto out;

WRITE_ONCE(io->task, get_task_struct(current));
ublk_mark_io_ready(ub);
-out:
+
+ return 0;
+}
+
+static int ublk_fetch(struct io_uring_cmd *cmd, struct ublk_device *ub,
+ struct ublk_io *io, __u64 buf_addr)
+{
+ int ret;
+
+ /*
+ * When handling FETCH command for setting up ublk uring queue,
+ * ub->mutex is the innermost lock, and we won't block for handling
+ * FETCH, so it is fine even for IO_URING_F_NONBLOCK.
+ */
+ mutex_lock(&ub->mutex);
+ ret = __ublk_fetch(cmd, ub, io);
+ if (!ret)
+ ret = ublk_config_io_buf(ub, io, cmd, buf_addr, NULL);
mutex_unlock(&ub->mutex);
return ret;
}
--
2.47.0